Method for coloring hair and other keratinaceous fibers with metal salts



United States Patent 3,215,605 METHOD FOR COLORHWG HAIR AND OTHERKERATINACEOUS FIBERS WITH METAL SALTS Saul Soloway, New Rochelle, N.Y.,assignor to Revlon, Inc., New York, N.Y. N0 Drawing. Filed Apr. 25,1962, Ser. No. 189,987 1 Claim. (Cl. 16788) This invention relates tothe coloring or dyeing of hair, fur, and similar keratinaceoussubstances or fibers and, more particularly, to effecting such coloringby means of metallic salt complexes applied directly to the material tobe colored or as chemically combined or linked to a pretreating agentpreviously applied to the hair or reacted with substances therein and/orwith or without additional color modification by a subsequently appliedreactant. I

As well known, of course, the dyeing or coloring or tinting of hair orfur has for years been carried out with a wide variety of dyes and othercoloring materials, although the dyeing or coloring of such materials,particularly to obtain a permanent and lasting effect, presents avariety of well recognized problems distinct from other natural orsynthetic fibers. Especially in the dyeing or coloring of growing humanhair (to which this invention is particularly adapted and which will beutilized in the following discussion as illustrative of the techniquesand objects to which this invention relates), certain particularlyexacting complications or problems may be encountered.

For example, although various metallic salt dyes and organic dyestuffsof both natural and synthetic varieties have been extensively used foryears in the dyeing of hair with more or less degrees of satisfaction, anumber of well recognized deficiencies and disadvantages obtain withsuch attempts, particularly with growing human hair. The difficulty ofobtaining natural appearing colors or shades or hues with metallic saltdyes is well recognized, particularly in instances where it is desiredthat the dyed product appear completely natural and not dyed. Organicdyestuffs, such as the widely used paraphenylenediamine-type ofmaterials, are highly toxic to many individuals and produce frequentadverse physiological effects so that, although satisfactorily used inthe dyeing of animal fur, widespread use in human hair dyeing istolerated primarily because of the general lack of anything better. Theshortcomings of other natural materials such as the henna-type dyes iswell understood, despite the fact that such materials have been used fordyeing human hair for literally thousands of years. Even with suchmaterials, however, difiiculty may be experienced in achieving adesirably natural-appearing shade or color, and especially in situationswhere the particular shade or color desired or dictated by the preceptsof a current fashion may be chemical dyeing reaction of conventionaldyestuffs with the various protein or amino acid materials which formthe keratinaceous hair fiber.

Even if it is possible to obtain a particularly desired hue or shadewith a blending of a variety of materials which might be described asdyestuffs, still other disadvantages may be experienced, particularlywith human hair, such as ancillary complications involving the necessityof maintaining a harshly alkaline pH for the dyeing reaction orunhealthful concomitants of necessary oxidation of the dye into theprotein-affinity form, etc. Similar complexities may be experienced withhair coloring techniques involving the production in situ of melanin asthe physiologically natural hair coloring material, particularly if itis desired to obtain a coloration in the reddish area and apart from thebrown or black hues naturally produced by melanin and/or of a reddish orother variety of color or shade which is either completely synthetic oroutside the spectrum of natural colors produced by physiologicalpigments other than melanin.

Especially as applied to the treatment of growing human hair (and asdistinct from the greater operational latitude permissible in thecoloring or dyeing of other animal fur, hair, or Wool fibers or otherkeratinaceous substances), substantial difiiculty may be experienced inachieving a desired hue or shade of coloration, whether by chemicalfiber dyeing or other coloring techniques, within the permissible areaof physiologically innocuous chemical reactions While still obtainingthe ultimate visual effect to approximate satisfaction in the user. Suchvisual satisfaction, as will be well understood, may be dictated bynon-technological considerations which superimpose upon the dyeing orcoloring technology virtually insuperable chemical problems involvingnot only the ultimate shade or hue of coloration achieved, but also thelustre and texture and tractability of the hair being treated, as wellas such considerations as the necessity for repeated and frequenttreatments of the same hair in order to accommodate the growth thereofand constant exposure of new lengths of untreated hair adjacent the skinfrom which the hair is growing.

According to this invention, by contrast, there is provided a system ortechnique and compositions for achieving on hair or fur or otherkeratinaceous substances a variety of effects of coloration or dyeingfor avoiding disadvantages heretofore encountered in connection withprior or conventional attempts to produce natural-appearing dyed effectswith either metallic salt or organic types of dyestuffs on suchmaterials or fibers with conventional dyeing or pigment-forming ormordanting techniques; and, in accordance with this invention, thedesired coloring effects are produced bya variety of metallic salt oroxide complexes, principally chemically combined or linked withpolypeptide components in the hair directly or with organic pretreatmentagents applied to and/ or reacted with components in the hair foraccepting the metallic complexes, which complexes as so linked orreacted with such materials either produce the desired degree andintensity of coloration or present for further reaction a potentiallycolorific group or materials susceptible to engendering the desiredcolor by subsequent chemical treatment. As more specifically statedfeatures of novelty, the teachings in accordance herewith include theactivation of or chemical combination with certain amino acid materialsin the hair by a pretreating agent to or with which complex salts ofcertain metals, particularly the transition metals of Group VIII of thePeriodic Table, form colored compounds or complexes and may combine,either to produce the finally desired ultimate color or to present a newchemical arrangement in or on the hair fibers which is susceptible tocolorific modification by aftertreatment with a variety of subsequentmodifying or complexing agents.

With the foregoing and other objects in view, this invention will now bemore particularly described, and other objects and advantages thereofwill be apparent from the following description and the appended claims.

As will be understood, of course, certain inorganic metallic salts maybe considered as inherently possessing certain colored or coloringqualities in water solution or otherwise, and some of them to someextent may be considered as having true dyeing propensities. Generally,however, the techniques and compositions in accordance with thisinvention are to be distinguished from such inherent qualities orpropensities of simple inorganic metal salts. That is, the simpletreatment of hair with aqueous solutions of metallic salts (no matterhow colorific they may be inherently) does not produce a dyeing orcoloring elTect of the stability or intensity 'or controllabilitydesired here for the particular coloring of human hair. For example, avariety of more or less impermanent colors or tints (in the sense thatthey can be more or less readily washed out by shampooing) may beimparted to human hair by applying thereto a variety of aqueoussolutions of many colored metallic inorganic compounds. Indeed, thereare even some instances where the mere application to reasonably blondor bleached hair of some simple aqueous solution of metal salts providesa distinct coloration of a more or less permanent nature--e.g., AuClalone imparts a bright yellow color to bleached human hair, whileaqueous solutions of cupric salts impart a more or less permanent lightgreen color. Nevertheless, such effects are to be distinguished from themost preferred advantages obtainable in accordance herewith.

This invention relates primarily to the achieving of the desiredcoloring or tinting effect utilizing a variety of metallic salts orcomplexes, particularly of the socalled transition metals, which can becaused to bind or link, one way or another, permanently to the hairmaterials to impart thereto colored elfects, whether or not theparticular shade or color is that normally associated as characteristicof the particular metal salt involved. Furthermore, treatments inaccordance herewith achieve the desired effects even with metallic saltmaterials which inherently have no particular afiinity for any of thematerials of which the hair is composed, and preferred results areattained in accordance herewith by the prior treatment of the hairand/or certain materials therein with a pretreating chemical agent orreactant so as to make available reactive valences or combining linkagesfor the reaction or addition of the colorific metallic complex toachieve the desired permanency, shade 'or hue, and texture.

For example, certain metallic salt materials with which satisfactoryresults are obtained in accordance herewith have been found not to havea particular colorific or propensity with previously untreated humanhair. Nevertheless, if the hair is first chemically treated as disclosedwith a variety of preliminary treating agents, a preliminary situationis created wherein a variety 'of metal salt solutions form chemicallycombined arrangements or complexes permanently with the hair. Among suchactivating or preliminary treatments may be noted, particularlyconventional alkaline peroxide bleaching techniques, which areparticular adapted for use in accordance herewith because a persondesiring to color hair frequently also wants to bleach the natural colorout of the hair as a preliminary step to achieving the ultimate shade orcolor desired.

Another, perhaps supplementary preliminary treatment material with whichsatisfactory results are achieved in accordance herewith is illustratedby a substance such as ammonium thioglycolate (hereinafter referred tofor brevity as ATG), which material is particularly adapted as apretreatment agent for application to previously bleached hair and asbeing representative of those materials which exhibit a ready reactivityfor one or more of the chemical linkages naturally occurring in humanhair so as to form, in addition to the desired color-reactive potentiallinkage, a material which also provides a certain amount of conditioningor softening or manageability to the hair being treated at leastsufficient to olfset any contrary characteristics produced by thecoloring treatment.

Thus, considering merely as illustrative of the treatments in accordanceherewith, the pretreatment results of utilizing ATG in hair coloringtechniques in accordance with this invention, one may note that asubstantial portion (perhaps 20%) of human hair is formed of materialsuch as cystine compounds having an RSSR- linkage, with the R being anamino acid radical. Reaction with ATG, with or without previous reactionin an alkaline peroxide bleaching step, breaks the RSSR linkage in thehair to produce ionizable or reactive -SH and RS and/or a different andionizable ammonium RSSR compound, some or all of which are readilyavailable to acquire and/ or combine with a metallic complex,particularly in alkaline solution, to an extent far greater than woud bethe case with merely attempting to react a metallic compound with thenatural and stable cystine material. Such preliminary reactions, then,make possible the integration or combining or complexing of a variety ofcolorific metallic salt solutions directly or permanently with the hairmaterials for producing a coloration thereon or, at least, a reactiveouter surface compound susceptible to color engendering or changing uponfurther chemical reaction. As will be apparent, such results areobtained in a mechanism which, generally, may be considered somewhatdifferent than any conventional dyeing technique and/or direct coloringtechniques in which solutions of simple inorganic metallic colored saltsmay be utilized.

As illustrative of such a sequential or complex reaction and theadvantages or results thereof, one may note the situation where amaterial such as a bivalent nickel salt in 5% water solution producessubstantially no discernible color change when applied to the hair aloneor to bleached hair, but the same solution of the metallic salt producesa quite discernible and brownish color when applied to hair which hasbeen previously bleached and treated with ATG, and a somewhat similarsituation occurs with cobalt compounds. Similarly, the gold chloridementioned above, while producing a bright yellow color when appliedinitially to bleached hair, produces a usable and satisfactorily naturalappearing golden or auburn coloration when applied to such hairpreviously treated with ATG in accordance herewith.

Also, it should be emphasized that the treatment of hair with AT G alonedoes not appear to produce any appreciab le change in coloration, anymore than is observed with the above noted nickel or cobalt solutionsalone, so the effect of coloring is achieved with a combination ofpreliminary chemical treatment and subsequent metallic complex and withdemonstrably true synergism. Furthermore, the preliminary reaction of acomplexing or pretreating agent such as ATG with the metal salts bymixing prior to the application of either to the hair fails to producethe coloring effect desired when applied to the hair, apparently becausesuch preliminary reaction complexes the metal ions with the ATG and allavailable valences thereof so as to leave few if any available reactivelinkage points for interaction or combining with the hair materials toproduce the permanent coloring effect desired.

As further illustrative of suitable materials with which techniquesembodying this invention may achieve satisfactory results, it may benoted that the metallic coloring agent involved (here referred to asmetallic complexes) may be produced particularly from the so-calledtransition metals of the Periodic Table, in aqueous or ammoniacal ororganic complexing environments. Thus, as noted above, merely a 5%aqueous solution of trivalent gold chloride produces the desiredsynergistic reaction with ATG-treated bleached hair, as do aqueoussolutions of a variety of other nickel, cobalt, cadmium, ferrous,ferric, cupric, etc., salts. Some of such materials also performadequately or differently, and in some cases more advantageously, whenutilized in ammoniacal solution, instead of merely aqueous solution, toform the desired metal complex for application to the previously treatedhair. In many such cases a different color or a different intensity orshade of color is provided when the metallic salt is applied in ammoniasolution instead of plain water, and different anions may give differenteffects for the same metal ion, especially as between anions ofdifferent valences. As noted below, in most if not all of suchsituations, the color or shade or intensity thereof can be furtherenhanced or changed or even removed by subsequently applying anadditional complexing agent after the metallic material is applied to orlinked on the hair and, in some cases, whether or not a preliminarycomplexing agent such at ATG was also utilized.

Generally in accordance herewith, a variety of metals have been foundsatisfactorily to react or combine with bleached hair, either directlyor after pretreatment thereof with a complexing material such as ATG,although some of the metals so reacted did not inherently produce anoticeable color change in hair. Nevertheless, the bonding or linking ofa metal ion or complex directly to the hair or to an intermediatetreatment compound combined therewith provides a situation where thecolor of the metallized hair may be subsequently modified to provide thecomplete advantages hereof whether or not a desirable color was obtainedby the metallizing treatment alone. The fact of reaction on the hair isreadily demonstrable (even when no discernible color change occurs),particularly with metals applied in the form of a salt which is coloredin aqueous solution, by noting the reduction in intensity of the colorof the solution as the reaction of the metal occurs with hair dippedinto the color solution, as well as by a visual metallic effectappearing in the hair surface.

Among the metals which reacted for complexing or binding to the hair inaccordance herewith, in aqueous or ammoniacal solution and with orwithout an initial or unaided color change, may be noted a variety ofmetallic ions including such metals as lithium, cesium, as well ascopper, silver, gold, magnesium, calcium, barium, zinc, cadmium, andmercury from the first two groups of the Periodic Table. Particularly ofinterest, however, are the transition metal elements or those which haveincomplete orbitals and a plurality of oxidation states such as those ofGroup VIII as well as such metals as lathamum and the lanthanide seriesof rare earths, the actinide series such as thorium, tin, and lead.Vanadium, bismuth, chromium, manganese, molybdenum, and uranium saltsalso were capable of complexing or binding results.

It was primarily the metals of Group VIII of the Periodic Table,however, which were found to produce the greatest or most useful colorchange in reaction with either the hair alone or with hair previouslytreated with a complexing agent such as ATG, and, particularly, iron,cobalt, nickel, palladium, and platinum. Although other Group VIIImetals achieved the desired reaction, the extreme rarity orexpensiveness of rhenium and iridium and the extreme toxicity of osmiumsalts indicate that these materials are not preferred, especially in thetreatment of growinghuman hair. As previously noted, of course, copperand gold salts give direct and useful color effects, although thesemetals are not in Group VIII of the Periodic Table, but the metals ofthis latter group are essentially those with which preferred results areachieved in accordance herewith when a primary color change is desiredupon initial application of either an aqueous or ammoniacal complex ofthe metal to the treated or untreated hair.

As previously noted, after application of the metal complex to the hairand the desired chemical bonding or linking thereto, some furthermodification of the color effect may then be achieved by a subsequenttreatment of the metallized hair by an additional complexing or treatingagent. As illustrative of such materials with which satisfactory resultsare achieved herewith may be noted such materials as an amidoxime ofcyanoethylcellulose polymers (referred to here for brevity as ADC) and/or thioamide materials or derivatives such as dithiooxamide (referred toas DTOA), etc. Although both the aforementioned materials or types ofmaterials do produce color variations or modifications as indicated inmore detail in the following data, the complexing or other mechanisms bywhich they each react on or affect the metallic materials linked to thehair may vary considerably, as will be understood.

enerally, as to visual effect, the subsequent application of additionalcomplexing agents or reactants to the metallized hair had the effect ofdeepening or darkening the color originally produced by the metal salt,although in some cases the actual color Was changed, rather than merelydeepening the original shade. In other cases (e.g., ferric salts) theoriginal color was actually lightened by subsequent application of amaterial uch as AOC. In other cases, the application of one or the otherof such materials as AOC or DTOA appeared to prevent or remove a colorchange obtained with the metal salt and only on activating pretreatment.

From the standpoint of the chemical reactions involved, it isessentially desired that the subsequent complexing agent react with themetal ion previously linked to the hair to form therewith a metalliccomplex of the desired color, which color will be different from thatoriginally produced by the reaction of the metallic salt with either thehair or a pretreating agent such as ATG thereon. With resin or polymertypes of subsequent complexing agents such as the AOC mentioned, avariety of tautomeric possibilities occur having different reactive orterminal groups available for complexing reaction with the previouslyapplied metal ion. That is, such materials are derived fromcyanoethylcellulose in known manner by, for example, reacting it withhydroxylamine to form, instead of the terminal CN group, eithertautomeric amidoxime group, which may react with various metal complexeson the hair to give a variety of different organo-metallic complexeshaving different colors and under different conditions.

Also, as will be understood, similar variations in conditions or colors,due to tautomerism or otherwise, may also be satisfactorily utilizedwith the materials such as DTOA or thiourea or other thioamides whereinthe shifting double bond linkages with either N or S in the terminal orreactant groupings provide for additional varieties of reactions andformation of metallic complexes of different colors with the metal ionspreviously applied to the hair and/or by complexing the originallyapplied metal salts with regard to the cystine linkages in the hairitself and/or the thioglycolate reaction therewith after pretreatmentwith ATG.

In any event, as will be apparent from the foregoing, the final coloreffects in accordance with this reaction may be achieved in almostinfinite variety and with a similar variety of different complexingmechanisms for producing colored metallic salt complexes chemicallylinked in one way or another to the substances in the hair. Especiallywith the use of a preliminary treatment of thio-glycolate (for reactionwith the --RSSR group in the cystine in the hair) and the subsequentutilization of thio-amine materials readily tautomerized in varionesolution media and at various pH ranges, -a large number of differentpossible permutations and combinations for the formation of differentlycolored metallic complexes is provided by the profusion of reactive Sand N groups and double bonds involved in the several noted types ofcompounds.

Indeed, the actual color effects obtained by the various differentcomplexing reactions possible may not be with certainty predicted inevery case, whether or not the chemistry is predictable, although thecolor effect have been found to be completely reproducible. That is, theparticular effects are readily discernible empirically for any givencombination of chemical substances, and the selected effects arethereafter completely reproducible in accordance herewith, whether onedesires to rely merely on the color change affected by the initialreaction of an aqueous or ammonia metallic complex with the hair or apretreatment complexing agent thereon or Whether it is desired to modifythis initial color condition further with a subsequent treatment of anadditional complexing agent as noted. Although the thio-types ofsubsequent complexing agents apparently produce a wider variety ofdifferent shades and color hues, it may actuaally be preferred to useone of the polymer types of complexing agents, such as AOC, because suchmaterials have an independent advantageous effect on the hair assoftening or conditioning agents, in addition to whatever effect theymay have in the coloring reactions, and are desirable additives to thecoloring technique for the purpose of aiding the later manageability ofthe hair, etc.

Merely as illustrative of some of the different coloring effectsachieved with various metallic salts and different complexing agents inaccordance herewith, the following Tables I and II collate the generalresults of a number of different treatment of essentially the sameinitially bleached human hair. In each instance the data is given withrespect to a variety of treatments with various metallic ions in aqueousor ammonia solution, with ATG being indicated as the preliminarycomplexing agent applied to the bleached hair prior to the metallic saltand with AOC and DTOA being shown as representative of subsequentlyapplied types of organic complexing agents.

Although data is given for instances Where no visibly appreciable colorchange was obtained, it is to be understood that additional or differentsubsequent complexing agents may be utilized, as will be understood fromthis disclosure, to produce other colored complexes with the appliedmetallic salt in a variety of different colors or shades. In allinstances the texture and sheen or appearance of the hair wassatisfactory, indeed usually to a greater extent than is normallyexperienced with conventional hair dyeing treatments, and the colorsachieved were the desirably natural appearing hair colors, with thepossible exception of the several instances noted in the greenishspectrum. Even these, however, were found to be further modified to morenatural hues by subsequent additions of various complexing agents.

In both Tables I and II, reading across, the 2; marks denote whether ornot a preliminary hair treatment with ATG and/ or subsequent complexingtreatments with AOC and DTOA were utilized with each of the notedmetallic salt complexes to provide the results noted. Table I sets forthillustrative data obtained using ammonia solution of the various saltsnoted, while the data of TABLE II relate to application of the metallicmaterials in aqueous solution, with a 5% concentration of salt in eachcase.

Table I Metal Salt in N HiOH Green.

Olive Green.

Black with greenish tinge. Dark reddish brown.

Lighter reddish brown.

Dark reddish brown.

Dark brown, slightly reddish. Darker brown.

Still darker brown.

Very dark brown.

Darllger brown (almost black). x o.

Table 11 A00 DTOA Color Results Dark yellow to auburn. Green'brown.

Dark green-brown. Bright yellow.

No color change. Slightly pink.

No (light change.

Slightly tan.

Light brown.

No color change.

Light brown.

Slightly tan.

Light green-brown. Darker green-brown. Black with greenish tinge. Nocolor change.

Do. Black with bluish tinge. Light green-brown. Darker green-brown. Darkred brown. N 0 color change. Slightly tan. Dark red brown. No colorchange.

Do. Light yellow. Light green.

0. Black with greenish tinge. Liglig green.

As Will be apparent from the foregoing tabulations, the ultimate coloreffect achieved with a particular metal salt is a truly synergisticfunction of the presence or absence of one or more pretreatments orafter treatments, with the former in one way or another breaking oractivating some sulphur (or, perhaps, some nitrogen) valences in thekeratinaceous material of the hair for compleXing reactivity orcombination with the metallic salt material.

It is to be understood, in considering the foregoing tabulations, thatall relate to the treatment of hair which has been previously bleachedwith conventional alkaline peroxide bleaching techniques, in the courseof which some activation of otherwise stable valences or chemicalbonding has occurred. For example, although gold chloride or cupricsalts produce a desirably permanent color effect (indicating truechemical complexing or combination with the hair) when applied to thebleached hair, a similarly permanent combination or result is notachieved with the same materials applied to hair which has notpreviously been subjected to some bleaching or chemical pretreatment.Furthermore, a further pretreatment, as with ATG or similarsulphur-reactive agents, in addition to reaction with the bleachingagent, produces still different complexing or color effects with thesame metallic salt solutions, just as additional after treatments withdifferent thio-amidic or other sulphur and nitrogen containing materialsalters the color efiect achieved and/ or changes or modifies in somemanner or other the particular metallic complex achieved with the hairmaterials. For example, considering the instances in the tabulationswhere the results are indicated as not producing the color change, suchnotation is to be understood as indicating merely that the particularmetallic complex achieved with the combination of materials noted doesnot produce an appreciable color on the bleached hair, whereas otherdifferent complexes of the same metal achieved With the differentcombinations of materials to produce a discernible color effect.

As will be apparent from the foregoing, a wide variety of materials arealso available for pretreating the hair to receive the desired coloringaction by metallic complexes, although, as noted, such materials mayfall broadly into the two categories of polymer-type materials and thosewhich actually react chemically with materials in the hair such as thecystine groups mentioned. Although the visible or coloring resultsachieved in either case may be substantially alike, it is to beunderstood that the particular mechanism whereby such results areachieved may vary. Thus, a variety of polymer-type materials (inaddition to those noted above) may be utilized as a pretreating oraftertreating complex material provided they also contain a multiplicityof functional groups in close proximity for bonding with a metalione.g., readily chelated materials, and/ or, particularly, those Withactive or available carboxy, hydroxy, amino, oxime, thio, cyano, etc.,groups.

Such functional groups are available for complexing the metallic salts,and, when included in a film forming or polymer-type material, are thususeful in accordance herewith. That is, such pretreatment or complexingagents form a coating or film layer over the hair (whether or not theymay also chemically react with the hair) as a basis for binding thecolorific metallic salts to form a more or less permanent colored layerbound to the hair. Although, for ease of application, water solublevarieties of such polymer or film forming materials produce satisfactoryresults in accordance herewith, it is preferred to utilize suchmaterials which tend to be insolubilized by the metallic salt complexingtherewith. Also, as will be understood for the particular utility here,absolute insolubility or permanence may not be necessary forsatisfactory results in view of the necessity for repeatedly treatingthe hair from time to time to maintain the artificial color thereof inany event and because the hair continues to grow and produce new areasadjacent the scalp requiring repeated treatment.

With the reactive or non-polymer types of pretreating materials noted(e.g., thio and dithio materials, peroxides, etc.) an actual chemicalreaction between such agents and the hair is believed to occur, asnoted, to open the -RSSR- linkage in one way or another and thus provideon the hair itself and from the materials therein an active sulphur (orsulfhydryl) group available for complexing the metal salt and/or anactive carboxy or hydroxy or other group. That is, the RSSR radical inthe hair is considered to react with one of the pretreating agents toproduce some active group on the RS of the original cystine hairmaterial, which group is available to bind metallic ions, while the SRgroup separated from the cystine radical also remains availableseparately to complex the metallic salts.

As will be understood, enhanced results may be achieved by utilizingpretreatment materials which both cling to the hair mechanically as filmforming polymers and also chemically react to open up the RSSR radicalto make available a plurality of complexing groups for binding thecolorific metallic ions. Similarly, the colored effects desired aregenerally achieved by metallic ions which will remain bound to the hairif combined with sulphur in some oxidation state thereof, and some suchmetals, upon complexing with a sulphur material, themselves formadditional active bonds for further complexing of additional metal ions.Therefore, in addition to purely mechanically bound complexing agents,there are also available generally in accordance herewith a wide varietyof materials which include various groups susceptible of nucleophilicdisplacement generally with dithio radicals. Among the classes ofmaterials, for example, which may combine both of the above mentionedmechanisms may be noted polymer-type esters of thio or cyano acids(e.g., a polyester of polyvinyl alcohol and thioglycolic acid or areactive polymeric ester of hydroxy ethyl cellulose and thioglycolicacid). Accordingly, there are available for use herewith materialshaving a plurality of complexing groups for reaction with colorificmetallic ions (e.g., hydroxyoxime, dioxime, dithio, thiohydrazide,diphenol, hydroxyamine, etc.) and some means for binding such reactivegroups (or other metal-complexing hy droxy, carboxy, thio, cyano, etc.,groups) more or less permanently to the hair-whether this last mentionedmeans includes mechanical binding as with a film forming polymer orchemical binding as by actual reaction with materials in the hair.Additionally, both of the foregoing can readily be combined into asingle material and, also, the invention includes the situation wherethe metal binding agency is wholly produced within the hair itself as byperoxide reaction with a pretreating material which contributes nothingmore to the final effect other than opening the RSSR linkage so it willreceive and bind colorific metal ions.

Accordingly there is provided in accordance herewith a wide variety ofmaterials and combinations of materials for application to human hair toproduce thereon a variety of different colors, shades, tints, or hues,all of a substantially permanent nature and resulting from differentmetallic salt complexes actually chemically bound to the hair materials.Furthermore, the methods and compositions involved are simply applied tothe air in solution, with the particular color effect being controlledprimarily by the combination of materials used, rather than being anotable function of reaction time or other delicate control techniquewhich might require extensive manipulative experience on the part of theperson applying the coloring material. Similarly, by contrast withconventional hair dyeing techniques and compositions, the materialsinvolved are free of adverse physiological toxic or sensitivity factors,are essentially innocuous in use and effect, with some of them actuallyimparting to the hair beneficial characteristics in addition tocoloring. Prior to application to the hair in the desired sequence, allthe various pretreatment and after treatment and metallic saltcompositions or components hereof are essentially stable and readilypackaged for convenient storage, sale, and handling, and the resultsachieved (both from the standpoint of permanency and specific coloreffect) are readily and repeatedly reproducible in a completely safe andcertain manner, even by untrained or unskilled users; and the effectivereactions involved for the application of the metallic salt materials,after treatment agents, etc., neither involve nor rely upon harshoxidation or reduction reactions or other chemistry of a nature whichmust be either critically controlled or considered as damaging to thehair being treated.

While the method and compositions herein described constitute preferredembodiments of the invention, it is to be understood that the inventionis not limited to these precise methods and compositions, and thatchanges may be made therein without departing from the scope of theinvention which is defined in the appended claim.

What is claimed is:

The method for coloring human hair and like keratinaceous fibers withcolorific metallic salt complexes, which comprises the steps ofpretreating said hair with a chem ical pretreating reactant for reactionwith -RSSR- groups in cystine materials in said hair to activatereactive complexing valences therein and selected from the groupconsisting of ammonium thioglycolate, polyesters of polyvinyl alcoholand thioglycolic acid, polyesters of hydroxy ethyl cellulose andthioglycolic acid, and mixtures thereof, applying an equeous solution ofa colorific complexing metal salt to said pretreated hair for reactionand complexing combination with said reactive valences thereof forforming a metallic complex chemically bonded to said pretreated hairsaid complexing metal salts being inorganic salts of metals selectedfrom the group consisting of lithium, caesium, copper, silver, gold,magnesium, calcium, barium, zinc, cadmium, mercury, the transitionmetals of Group VIII of the Periodic Table, the lanthanide series ofrare earth metals, the actinide series of metals, tin, lead, vanadium,bismuth, chromium, manganese, molybdenum, uranium, and mixtures thereof,and thereafter treating said metallic complex on said hair with anadditional complexing agent for altering the visible color effect ofsaid metallic complex as bound on said hair, said additional complexingagent being selected from the group consisting of dithiooxamide,amidoxines of cyanoethyl cellulose polymers, polyesters of thioglycolicacid, and mixtures thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,501,184 3/50Michaels 167-88 12 2,615,782 10/52 Haefele 167-88 XR 2,719,104 9/55Westerberg 167-88 2,769,748 11/56 Eckardt et al. 167-88 2,934,396 4/60Charle et a1 167-88 XR 2,948,657 8/60 Siccama et al. 167-88 XR 3,062,60911/ 62 Abel 8-43 3,063,950 11/62 Schouteden 260-212 XR 3,066,077 11/ 62De Mytt et al 167-871 3,075,821 1/63 Goldemberg et al. 167-88 XR FOREIGNPATENTS 163,316 6/55 Great Britain.

OTHER REFERENCES Encyclopedia of Chemical Technology, 14: 173-177(1955).

Goldemberg: Journal of the Society of Cosmetic Chemists, 10: 294, 296,and 301-302 (1959).

Greenfield: Journal of the Society of Cosmetic ChemiSts, 8(4): 200, 201,205, and 209 (1957).

Rostenberg et al.: Todays Health, vol. 48, No. 8, pp. 14-17 and 68-71,especially pages 16 and 17 (1964).

Wilsmann: American Perfumer and Aromatics, (5), p. 46, May 1960.

JULIAN S. LEVITT, Primary Examiner.

FRANK CACCIAPAGLIA, L. GOTTS, Examiners.

